Almost exactly two years ago, all SPS equipment was switched off and responsibility for the machine was handed from the Operations (OP) group in the Beams (BE) department to the Accelerator Coordination and Engineering (ACE) group in the Engineering (EN) department.

Despite the SPS not accelerating particles, the tunnel was buzzing with action during Long Shutdown 2 (LS2). Many parts of the machine were taken apart and renewed or consolidated with the aim of increasing its performance and reliability.

On 4 December 2020, exactly as scheduled, members of the EN-ACE group concluded their task of coordinating, in close collaboration with all the equipment and service groups, the LS2 activities by handing the key of the upgraded SPS back to BE-OP, signalling the start of the hardware commissioning period. During this nine-week period, the operations teams, working closely with the equipment experts, will make sure every piece of equipment and its associated software are working according to specifications. Then there will be a six-week cold check-out period, where the machine will run as if beams were being produced, but without particles, checking that everything is working in harmony like a finely tuned orchestra.

On 12 April 2021, the SPS will have to be ready to receive the first beams from the PS to commission all beams required for physics, so that the experimentalists in the SPS North Area can resume their physics data taking on 12 July 2021.